<template>
    <div id="aCoursesList" class="bg-fa of">
        <!-- /课程列表 开始 -->
        <section class="container">
            <header class="comm-title">
                <h2 class="fl tac">
                    <span class="c-333">全部课程</span>
                </h2>
            </header>
            <section class="c-sort-box">
                <section class="c-s-dl">
                    <dl>
                        <dt>
                            <span class="c-999 fsize14">课程类别</span>
                        </dt>
                        <dd class="c-s-dl-li">
                            <ul class="clearfix">
                                <li>
                                    <a title="全部" href="#">全部</a>
                                </li>
                                <li v-for="(item,index) in subjectNestedList" :key="index" :class="{active:oneIndex==index}">
                                    <a :title="item.title" href="#" @click="searchOne(item.id,index)">{{ item.title }}</a>
                                </li>
                            </ul>
                        </dd>
                    </dl>
                    <dl>
                        <dt>
                            <span class="c-999 fsize14"></span>
                        </dt>
                        <dd class="c-s-dl-li">
                            <ul class="clearfix">
                                <li v-for="(item,index) in subSubjectList" :key="index" :class="{active:twoIndex==index}">
                                    <a :title="item.title" href="#" @click="searchTwo(item.id,index)">{{item.title}}</a>
                                </li>
                            </ul>
                        </dd>
                    </dl>
                    <div class="clear"></div>
                </section>
                <div class="js-wrap">
                    <section class="fr">
                        <span class="c-ccc">
                            <i class="c-master f-fM">1</i>/
                            <i class="c-666 f-fM">1</i>
                        </span>
                    </section>
                    <section class="fl">
                        <ol class="js-tap clearfix">
                            <li :class="{'current bg-orange':buyCountSort!=''}">
                                <a title="销量" href="javascript:void(0);" @click="searchBuyCount()">销量
                                <span :class="{hide:buyCountSort==''}">↓</span>
                                </a>
                            </li>

                            <li :class="{'current bg-orange':gmtCreateSort!=''}">
                                <a title="最新" href="javascript:void(0);" @click="searchGmtCreate()">最新
                                <span :class="{hide:gmtCreateSort==''}">↓</span>
                                </a>
                            </li>

                            <li :class="{'current bg-orange':priceSort!=''}">
                                <a title="价格" href="javascript:void(0);" @click="searchPrice()">价格&nbsp;
                                <span :class="{hide:priceSort==''}">↓</span>
                                </a>
                            </li>
                        </ol>
                    </section>
                </div>
                <div class="mt40">
                    <!-- /无数据提示 开始-->
                    <section class="no-data-wrap" v-if="data.total==0">
                        <em class="icon30 no-data-ico">&nbsp;</em>
                        <span class="c-666 fsize14 ml10 vam">没有相关数据，小编正在努力整理中...</span>
                    </section>
                    <!-- /无数据提示 结束-->
                    <article class="comm-course-list" v-if="data.total>0">
                        <ul class="of" id="bna">
                            <li v-for="item in data.items" :key="item.id">
                                <div class="cc-l-wrap">
                                    <section class="course-img">
                                        <img :src="item.cover" class="img-responsive" :alt="item.title">
                                        <div class="cc-mask">
                                            <a :href="'/course/'+item.id" title="开始学习" class="comm-btn cbtn-1">开始学习</a>
                                        </div>
                                    </section>
                                    <h3 class="hLh30 txtOf mt10">
                                        <a :href="'/course/'+item.id" :title="item.title" class="course-title fsize18 c-333">{{item.title}}</a>
                                    </h3>
                                    <section class="mt10 hLh20 of">
                                        <span class="fr jgTag bg-green" v-if="Number(item.price) === 0">
                                            <i class="c-fff fsize12 f-fA">免费</i>
                                        </span>
                                        <span class="fl jgAttr c-ccc f-fA">
                                            <i class="c-999 f-fA">9634人学习</i>
                                            |
                                            <i class="c-999 f-fA">9634评论</i>
                                        </span>
                                    </section>
                                </div>
                            </li>
                        </ul>
                        <div class="clear"></div>
                    </article>
                </div>

                <!-- 公共分页 开始 -->
                <div>
                    <div class="paging">
                    <!-- undisable这个class是否存在，取决于数据属性hasPrevious -->
                    <a
                        :class="{ undisable: !data.hasPrevious }"
                        href="#"
                        title="首页"
                        @click.prevent="gotoPage(1)">首</a>
                    <a
                        :class="{ undisable: !data.hasPrevious }"
                        href="#"
                        title="前一页"
                        @click.prevent="gotoPage(data.current - 1)">&lt;</a>
                    <a
                        v-for="page in data.pages"
                        :key="page"
                        :class="{ current: data.current == page, undisable: data.current == page }"
                        :title="'第' + page + '页'"
                        href="#"
                        @click.prevent="gotoPage(page)">{{ page }}</a>
                    <a
                        :class="{ undisable: !data.hasNext }"
                        href="#"
                        title="后一页"
                        @click.prevent="gotoPage(data.current + 1)">&gt;</a>
                    <a
                        :class="{ undisable: !data.hasNext }"
                        href="#"
                        title="末页"
                        @click.prevent="gotoPage(data.pages)">末</a>
                    <div class="clear"/>
                    </div>
                </div>
                <!-- 公共分页 结束 -->
            </section>
        </section>
        <!-- /课程列表 结束 -->
    </div>
</template>
<script>
import courseApi from '@/api/course'

export default {
    data() {
        return {
            page: 1,
            data: {},
            subjectNestedList: [], // 一级分类列表
            subSubjectList: [], // 二级分类列表

            searchObj: {}, // 查询表单对象

            oneIndex: -1,
            twoIndex: -1,
            buyCountSort: "",
            gmtCreateSort: "",
            priceSort: ""

        }
    },
    created(){
        // 课程第一次查询
        this.initCourseFirst()
        this.initSubject()
    },
    methods: {
        //1 查询第一页数据
        initCourseFirst() {
            courseApi.getCourseList(1, 8, this.searchObj)
                .then(response => {
                    this.data = response.data.data
                })
        },

        //2 查询所有的分类
        initSubject() {
            courseApi.getAllSubject(1, 8, this.searchObj)
                .then(response => {
                    this.subjectNestedList = response.data.data.list
                })
        },

        //3 分页切换的方法
        gotoPage(page) {
            courseApi.getCourseList(page, 8, this.searchObj)
                .then(response => {
                    this.data = response.data.data
                })
        },

        //4 点击某个一级分类，展示对应的二级分类
        searchOne(subjectParentId,index) {
            //把传递 index 值赋值给 oneIndex ，为了active样式生效
            this.oneIndex = index

            this.twoIndex = -1
            this.searchObj.subjectId = ""
            this.subSubjectList = []

            //把点击的一级分类id值，赋值给 searchObj
            this.searchObj.subjectParentId = subjectParentId
            //点击某个一级分类进行条件查询
            this.gotoPage(1)
            
            //拿点击的一级分类的 id 和 所有一级分类的 id 进行对比
            //如果id相同，从一级分类里面获取对应的二级分类
            for (let i = 0; i < this.subjectNestedList.length; i++) {
                //获取每一个一级分类
                const element = this.subjectNestedList[i];
                //比较id是否相同
                if (subjectParentId == element.id) {
                    //从一级分类里面获取对应的二级分类
                    this.subSubjectList = element.children
                }
            }
        },

        //5 点击某个二级分类，展示对应的信息
        searchTwo(subjectId,index) {
            //把传递 index 值赋值给 twoIndex ，为了active样式生效
            this.twoIndex = index

            //把点击的二级分类id值，赋值给 searchObj
            this.searchObj.subjectId = subjectId
            //点击某个二级分类进行条件查询
            this.gotoPage(1)
        },

        //6 根据销量排序
        searchBuyCount(){
            //设置对应的变量的值，为了样式生效
            this.buyCountSort = "1"
            this.gmtCreateSort = ""
            this.priceSort = ""

            //把值设置给 subjectObj
            this.searchObj.buyCountSort = this.buyCountSort
            this.searchObj.gmtCreateSort = this.gmtCreateSort
            this.searchObj.priceSort = this.priceSort

            //调用方法
            this.gotoPage(1)
        },

        //7 根据最新排序
        searchGmtCreate() {
            //设置对应的变量的值，为了样式生效
            this.buyCountSort = ""
            this.gmtCreateSort = "1"
            this.priceSort = ""

            //把值设置给 subjectObj
            this.searchObj.buyCountSort = this.buyCountSort
            this.searchObj.gmtCreateSort = this.gmtCreateSort
            this.searchObj.priceSort = this.priceSort

            //调用方法
            this.gotoPage(1)
        },

        //8 根据销量排序
        searchPrice() {
            //设置对应的变量的值，为了样式生效
            this.buyCountSort = ""
            this.gmtCreateSort = ""
            this.priceSort = "1"

            //把值设置给 subjectObj
            this.searchObj.buyCountSort = this.buyCountSort
            this.searchObj.gmtCreateSort = this.gmtCreateSort
            this.searchObj.priceSort = this.priceSort

            //调用方法
            this.gotoPage(1)
        }
    }
};
</script>
<style scoped>
.active {
background: #bdbdbd;
}
.hide {
display: none;
 }
.show {
display: block;
 }
</style>